package com.weixin.sdk.kit;

import org.apache.commons.lang3.StringUtils;

import javax.net.ssl.*;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.Map;
import java.util.Map.Entry;

/**
 * wjun_java@163.com
 * 2016年6月5日
 */
public class HttpKit {
    private HttpKit() {
    }

    /**
     * https 域名校验
     */
    private class TrustAnyHostnameVerifier implements HostnameVerifier {
        public boolean verify(String hostname, SSLSession session) {
            return true;
        }
    }

    /**
     * https 证书管理
     */
    private class TrustAnyTrustManager implements X509TrustManager {
        public X509Certificate[] getAcceptedIssuers() {
            return null;
        }

        public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
        }

        public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
        }
    }

    private static final String GET = "GET";
    private static final String POST = "POST";
    private static String CHARSET = "UTF-8";

    private static final SSLSocketFactory sslSocketFactory = initSSLSocketFactory();
    private static final TrustAnyHostnameVerifier trustAnyHostnameVerifier = new HttpKit().new TrustAnyHostnameVerifier();

    private static SSLSocketFactory initSSLSocketFactory() {
        try {
            TrustManager[] tm = {new HttpKit().new TrustAnyTrustManager()};
            SSLContext sslContext = SSLContext.getInstance("TLS");    // ("TLS", "SunJSSE");
            sslContext.init(null, tm, new java.security.SecureRandom());
            return sslContext.getSocketFactory();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    public static void setCharSet(String charSet) {
        if (StringUtils.isBlank(charSet)) {
            throw new IllegalArgumentException("charSet can not be blank.");
        }
        HttpKit.CHARSET = charSet;
    }

    private static HttpURLConnection getHttpConnection(String url, String method, Map<String, String> headers) throws IOException, NoSuchAlgorithmException, NoSuchProviderException, KeyManagementException {
        URL _url = new URL(url);
        HttpURLConnection conn = (HttpURLConnection) _url.openConnection();
        if (conn instanceof HttpsURLConnection) {
            ((HttpsURLConnection) conn).setSSLSocketFactory(sslSocketFactory);
            ((HttpsURLConnection) conn).setHostnameVerifier(trustAnyHostnameVerifier);
        }

        conn.setRequestMethod(method);
        conn.setDoOutput(true);
        conn.setDoInput(true);

        conn.setConnectTimeout(19000);
        conn.setReadTimeout(19000);

        conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
        conn.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/33.0.1750.146 Safari/537.36");

        if (headers != null && !headers.isEmpty())
            for (Entry<String, String> entry : headers.entrySet())
                conn.setRequestProperty(entry.getKey(), entry.getValue());

        return conn;
    }

    /**
     * Send GET request
     */
    public static String get(String url, Map<String, String> queryParas, Map<String, String> headers) {
        HttpURLConnection conn = null;
        try {
            conn = getHttpConnection(buildUrlWithQueryString(url, queryParas), GET, headers);
            conn.connect();
            return readResponseString(conn);
        } catch (Exception e) {
            throw new RuntimeException(e);
        } finally {
            if (conn != null) {
                conn.disconnect();
            }
        }
    }

    public static String get(String url, Map<String, String> queryParas) {
        return get(url, queryParas, null);
    }

    public static String get(String url) {
        return get(url, null, null);
    }

    /**
     * Send POST request
     */
    public static String post(String url, Map<String, String> queryParas, String data, Map<String, String> headers) {
        HttpURLConnection conn = null;
        try {
            conn = getHttpConnection(buildUrlWithQueryString(url, queryParas), POST, headers);
            conn.connect();

            OutputStream out = conn.getOutputStream();
            out.write(data.getBytes(CHARSET));
            out.flush();
            out.close();

            return readResponseString(conn);
        } catch (Exception e) {
            throw new RuntimeException(e);
        } finally {
            if (conn != null) {
                conn.disconnect();
            }
        }
    }

    public static String post(String url, Map<String, String> queryParas, String data) {
        return post(url, queryParas, data, null);
    }

    public static String post(String url, String data, Map<String, String> headers) {
        return post(url, null, data, headers);
    }

    public static String post(String url, String data) {
        return post(url, null, data, null);
    }

    private static String readResponseString(HttpURLConnection conn) {
        StringBuilder sb = new StringBuilder();
        InputStream inputStream = null;
        try {
            inputStream = conn.getInputStream();
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, CHARSET));
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line).append("\n");
            }
            return sb.toString();
        } catch (Exception e) {
            throw new RuntimeException(e);
        } finally {
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    /*LogKit.error(e.getMessage(), e);*/
                }
            }
        }
    }

    /**
     * Build queryString of the url
     */
    private static String buildUrlWithQueryString(String url, Map<String, String> queryParas) {
        if (queryParas == null || queryParas.isEmpty())
            return url;

        StringBuilder sb = new StringBuilder(url);
        boolean isFirst;
        if (url.indexOf("?") == -1) {
            isFirst = true;
            sb.append("?");
        } else {
            isFirst = false;
        }

        for (Entry<String, String> entry : queryParas.entrySet()) {
            if (isFirst) isFirst = false;
            else sb.append("&");

            String key = entry.getKey();
            String value = entry.getValue();
            if (StringUtils.isNotBlank(value))
                try {
                    value = URLEncoder.encode(value, CHARSET);
                } catch (UnsupportedEncodingException e) {
                    throw new RuntimeException(e);
                }
            sb.append(key).append("=").append(value);
        }
        return sb.toString();
    }
	
	/*public static String readData(HttpServletRequest request) {
		BufferedReader br = null;
		try {
			StringBuilder result = new StringBuilder();
			br = request.getReader();
			for (String line=null; (line=br.readLine())!=null;) {
				result.append(line).append("\n");
			}
			
			return result.toString();
		} catch (IOException e) {
			throw new RuntimeException(e);
		}
		finally {
			if (br != null)
				try {br.close();} catch (IOException e) {LogKit.error(e.getMessage(), e);}
		}
	}
	
	@Deprecated
	public static String readIncommingRequestData(HttpServletRequest request) {
		return readData(request);
	}*/
}
